The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 29, 1976
Filed:
Sep. 24, 1974
Applicant:
Inventors:
Jean-Pierre G Senet, Vaux-le-Penil, FR;
Julien C Deweerdt, Toulouse, FR;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
260463 ;
Abstract
Hydroxy-telechelating oligomers of number average molecular weight 250 to 2,500 and containing carbonate groups, are prepared by first polycondensing a bis-chloroformate with a diol at a temperature below 150.degree.C and at a moderately reduced pressure while flushing the reaction mixture with an inert anhydrous gas, and then the oligomers formed are dissolved in a volatile, water-immiscible organic solvent and the solution washed with an aqueous base solution. In this way, oligomers may be prepared which have a low or zero sensitivity to water, are non-acidic and relatively inexpensive.